U.S. patent number 4,770,453 [Application Number 07/093,445] was granted by the patent office on 1988-09-13 for mounting structure for vehicle bumper assembly.
This patent grant is currently assigned to Chrysler Motors Corporation. Invention is credited to Thomas Reynolds.
United States Patent |
4,770,453 |
Reynolds |
September 13, 1988 |
Mounting structure for vehicle bumper assembly
Abstract
Adjustment means are provided to properly position a vehicle
bumper assembly. The vehicle bumper assembly includes bumper
structure and energy absorbing devices which mount it to vehicle
structure. The adjustment means comprise threaded structure
permitting rotative motion to move the energy absorbing devices in
an axial direction. The threaded structure is adapted to move the
bumper assembly a predetermined measured amount measured by opening
means which provide for detachable fastening of the assembly in
place.
Inventors: |
Reynolds; Thomas (Troy,
MI) |
Assignee: |
Chrysler Motors Corporation
(Highland Park, MI)
|
Family
ID: |
22239004 |
Appl.
No.: |
07/093,445 |
Filed: |
September 4, 1987 |
Current U.S.
Class: |
293/119; 293/132;
293/155 |
Current CPC
Class: |
B60R
19/26 (20130101); B60R 2019/245 (20130101) |
Current International
Class: |
B60R
19/26 (20060101); B60R 19/24 (20060101); B60R
019/24 () |
Field of
Search: |
;293/119,121,126,132,134,155 ;411/172,432,427 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
119052 |
|
Oct 1944 |
|
AU |
|
682498 |
|
Nov 1952 |
|
GB |
|
Primary Examiner: Pedder; Dennis H.
Attorney, Agent or Firm: Craig; Edward A.
Claims
I claim:
1. In a vehicle bumper assembly comprising a bumper structure for
receiving impact forces, at least one energy absorbing device
secured between the bumper structure and vehicle support structure
to mount said bumper structure, the energy absorbing device
including a cylinder detachably fastened to said vehicle support
structure, a piston slidably received within the cylinder, the
piston being detachably fastened at an outer end thereof to the
bumper structure, the improvement comprising an externally threaded
portion on the cylinder intermediate the ends thereof and having a
diameter larger than the diameter of said cylinder, an internally
threaded collar threadingly received on said threaded portion, at
least one of the collar and said outer end of the piston having a
radially outwardly extending flange portion, the flange portion
having at least two circumferentially spaced apart openings
therein, a respective one of said vehicle structure and bumper
structure having mating openings therein, the spacing of the
openings being related to the pitch of said threaded portion so
that relative turning of the cylinder and collar from a position
where the openings mate to a second position where the openings
again mate results in a predetermined measured amount of axial
movement of the energy absorber with respect to the collar which
movement represents a desired final positional alignment of the
bumper structure with respect to the vehicle support structure, the
mating openings receiving detachable fastening means to detachably
secure the respective elements together.
2. The vehicle bumper assembly of claim 1, further characterized in
that said flange portion is provided on the collar and said mating
openings are provided in the vehicle support structure.
3. The vehicle bumper assembly of claim 1, further characterized in
that said flange portion is provided on the outer end of the piston
and said mating openings are provided in the bumper structure.
4. The vehicle bumper assembly of claim 1, further characterized in
that a flange portion having at least two circumferentially spaced
apart openings therein is provided on both the collar and on the
outer end of the piston and each of said vehicle support structure
and said bumper structure has mating openings for, respectively,
the spaced apart openings in the flange portion on the collar and
the spaced apart openings in the flange portion on the outer end of
the piston.
5. The vehicle bumper assembly of claim 1, further characterized in
that the predetermined measured amount of axial movement of the
energy absorber with respect to the collar upon relative turning of
the cylinder and collar from a position where the openings mate to
a second position where the openings again mate is about one
millimeter.
Description
BACKGROUND OF THE INVENTION
1. Field of Invention
The invention relates to mounting structure for a vehicle bumper
assembly which permits desired positionment of the bumper assembly
with respect to the main vehicle structure by manipulation of
threaded means.
2. Prior Art
Government regulations have mandated that front and rear bumpers of
vehicles be so constructed and mounted as not to be damaged as a
consequence of low speed impact with other vehicles or fixed
structure. The prevailing method for accomplishing this is to mount
the bumper onto a vehicle by means of an energy absorbing device,
such as a shock absorbing structure. When the bumper is impacted at
low speeds, the energy absorbing device collapses, absorbing the
energy of impact. This collapse takes with it the bumper which
moves towards the vehicle. After being impacted, the energy
absorbing devices bias the bumper back to its normal position.
One problem which has been encountered in connection with the
mounting of vehicle bumper assemblies including energy absorbers
has been proper alignment of the bumper assembly with other
portions of the vehicle. This problem has been particularly acute
with respect to alignment of the end portions of the bumpers with
fender structure of a vehicle. Modern perceptions of "fit and
finish" do not permit the existence of any substantial gaps between
adjacent outer body panels. One method for adjusting the
positionment of the bumper has been the use of shims between the
energy absorbers and the bumper structure. This technique is
discussed in U.S. Pat. No. 4,160,561, Farnam et al, July 10, 1979,
entitled "Vehicle Bumper Shim and Method".
Another technique which has been employed to eliminate the
appearance of a gap between the bumper structure and vehicle
fenders has been to provide a flexible panel portion on each end of
the bumper. This flexible portion has been long enough to extend
slightly over the adjacent vehicle fenders so that even if the
bumper structure is not close enough to the fenders to prevent the
presence of a gap, the gap is covered by the overlapping panel
structure. This is objectionable from a style standpoint because it
adds an extra vertical line to the vehicle body structure which is
not part of the coordinated design intended by the stylist.
Alternately, overlap has been avoided by directly attaching the
flexible panels to the fender. However, this has sometimes resulted
in objectionable appearance (wrinkles or bulges) or has required a
floating attachment of the bumper facia to a bumper beam.
The present invention provides an alternate means for mounting the
bumper assembly by use of support structure including threaded
means which permit forward or rearward adjustment of the bumper
assembly as desired. Use of threaded means to permit bumper
adjustment has been broadly suggested in the past, as for example,
U.S. Pat. No. 1,565,785, Buck, Dec. 15, 1925 and U.S. Pat. No.
1,646,055 Ebaugh, Oct. 18, 1927. However, the present invention
provides a refined version which permits accurate, measured
adjustment of the bumper assembly to achieve the desired final
aligned position of the bumper structure. The adjusting means
permits limited forward or rearward adjustment and includes two
separate structures which permit manipulation of the energy
absorbing device, one without the bumper attached and the other
with the bumper attached, the technique used depending upon the
configuration of vehicle support structure which is
encountered.
SUMMARY OF THE INVENTION
The vehicle bumper assembly comprises a bumper structure for
receiving impact forces. An energy absorbing device is secured
between the bumper structure and vehicle support structure to mount
the bumper structure. The energy absorbing device includes a
cylinder which is detachably fastened to vehicle support structure.
A piston is slidably received in the cylinder. The piston is
detachably fastened at the outer end thereof to the bumper
structure. Means are provided within the cylinder to absorb energy
upon impact of the bumper with subsequent movement of the piston
into the cylinder. This structure is improved in accordance with
the present invention by providing an externally threaded portion
on the cylinder intermediate the ends thereof. An internally
threaded collar is threadingly received on said threaded portion.
At least one of the collar and outer end of the piston has a
radially outwardly extending flange portion. The flange portion is
provided with at least two circumferentially spaced apart openings
therein. The respective one of said vehicle structure and said
bumper structure has mating openings therein.
The spacing of the openings is related to the pitch of the threaded
portion so that relative turning of the cylinder and collar from a
position where the openings mate to a second position where the
openings again mate results in a predetermined measured amount of
axial movement of the energy absorber with respect to the collar,
which movement represents a desired final positional alignment of
the bumper structure with respect to the vehicle. Preferably, this
movement is about one millimeter. Also, preferably a flange
structure is provided along with mating openings in the vehicle
structure on both the collar and the outer end of the piston. The
mating openings receive fastening means to detachably secure the
respective elements together.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a view in perspective of a vehicle illustrating one
embodiment of the vehicle bumper assembly of the present invention
mounted on the front end thereof;
FIG. 2 is a sectional view taken substantially along the line 2--2
of FIG. 1 looking in the direction of the arrows;
FIG. 3 is a top plan view of the front end portion of the vehicle
of FIG. 1;
FIG. 4 is a sectional view taken along the line 4--4 of FIG. 2
looking in the direction of the arrows; and
FIG. 5 is a sectional view taken substantially along the line 5--5
of FIG. 2 looking in the direction of the arrows.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 3, it will be noted that a vehicle bumper
assembly 10 is mounted on the front end of a vehicle 12, shown as
an automobile. The vehicle bumper assembly 10 may, however, be
mounted on other vehicle forms, such as light trucks, vans and the
like. Additionally, the vehicle bumper assembly 10 may be mounted
on the rear of the vehicle 12 as well as on the front.
The vehicle bumper assembly 10 includes a conventional bumper beam
14 which functions as a structural member for receiving impact
forces which may be encountered as a consequence of hitting another
vehicle or a fixed object. The bumper beam 14 has fixed thereto a
soft bumper facia 16 which is essentially ornamental. As will be
noted, the facia 16 extends across the front of the vehicle 12 and
has end portions 18, 20 which extend around the sides of the
vehicle for a short distance. The end portions 18, 20 may be longer
or shorter than illustrated. They terminate at the edge of sheet
metal defining fenders 22, 24. A line 26 is defined at this
juncture. Portions 18, 20 are conventionally attached to fenders
22, 24 at juncture 26.
A pair of spaced apart energy absorbing devices 28, 30 are secured
to the bumper beam 14 to complete the vehicle bumper assembly 10.
The energy absorbing devices bias the bumper structure to a normal
position as shown in the figures. Each energy absorbing device
comprises a cylinder 32 which is detachably fastened to vehicle
support structure 34, the structure 34 being a structural rail
forming part of the vehicle framing. A piston 36 is slidably
received in the cylinder 32. The piston 36 is detachably fastened
at the outer end 38 thereof to the bumper beam 14. As is common in
the art, means are provided within the cylinder 32 to absorb energy
upon impact of the bumper which results in subsequent movement of
the piston 36 into the cylinder 32. The energy absorbing means may
be hydraulic, pneumatic, a compressible composition, such as a
springy plastic material, or the like. The specific type of energy
absorbing device is not germane to the present invention, the
present invention functioning with various styles of such devices.
The energy absorbing devices permit movement of the bumper a short
distance towards the vehicle on which they are mounted after a low
speed impact with another vehicle or stationary structure without
appreciable damage to the bumper structure. After the impacting
force is dissipated, the bumper structure is returned to its
original position by the energy absorbing devices. As above
mentioned, such bumper mounting constructions are common in the
automotive industry at this time.
As will be noted in FIG. 2, an externally threaded portion 40 is
provided on the cylinder 32 intermediate the ends thereof. The
externally threaded portion comprises a tubular structure having
the threads provided on the outer surface thereof. This structure
is slidingly received over the cylinder 32 and fixed in place as by
welding at 42.
An internally threaded collar 44 is threadingly received on
threaded portion 40. As will be noted in FIGS. 2 and 4, the collar
44 has a radially outwardly extending flange portion 46. Two
circumferentially spaced apart openings 48, 50 are provided in the
flange portion 46. The vehicle structure 34 has mating threaded
openings 51, 53 therein which receive threaded bolts 52, 54 to
detachably secure the collar 34 to the structure 34.
The outer end 38 of the piston 36 has similar structure for
detachable fastening to the bumper beam 14. As will be noted, a
bracket 56 is secured to the outer end of the piston. The bracket
56, as shown in FIGS. 2 and 5, has a radially outwardly extending
flange portion 58 in which are provided two circumferentially
spaced apart openings 60, 62. Mating threaded openings 64, 66 are
provided in the bumper beam 14. Threaded bolt structures 68, 70
pass through openings 60, 62 and are threadingly received in
openings 64, 66 to detachably secure the outer end 38 of the piston
36 to the bumper beam 14.
It will thus be appreciated that the collar 44 acts to detachably
fasten the cylinder 32 to vehicle support structure and the bracket
56 acts to detachably secure the piston 36 to the bumper beam
14.
As will be noted in FIG. 2, the cylinder 32 extends beyond support
structure 34 and terminates in a stem 72. The stem 72 has an
isolator cap 74 thereon, the cap 74 being preferably fabricated of
a plastic material. The cap 74 is slidingly received in an opening
76 provided in vehicle support structure 78. This structure acts as
stabilizing means for the energy absorbing devices, it being
appreciated that each energy absorbing device 28, 30 is mounted in
like manner, thus ensuring proper alignment of the bumper structure
and proper action of the energy absorbing devices when needed.
During adjustment of the bumper assembly, the cap 74 is free to
slide in the opening 76 to accommodate axial movement of the energy
absorbing device.
The spacing of the openings 48, 50 and the mating openings 51, 53
and also the openings 60, 62 and mating openings 64, 66 is related
to the pitch of the threaded portion 40 (and thus also to the
internal threads of the collar 44) so that relative turning of the
cylinder 32 and collar 44 from a position where the openings meet
to a second position where the openings again meet results in a
predetermined measured amount of axial movement of the energy
absorber with respect to the collar which movement represents a
desired final positional alignment of the bumper structure with
respect to the vehicle. The preferred amount of movement of the
energy absorber from the position where the openings mate to a
second position wherein the openings again mate is one millimeter.
This is accomplished in an actual embodiment with a thread
specification as follows: M54X2.00 ISO CLASS 6 g THD. It is thus
possible to adjust the bumper structure so that any gap between the
end portions 18, 20 and fenders 22, 24 will be no more than one
millimeter. Additionally, it is possible to predetermine the number
of necessary turns of the threads in order to bring the desired
alignment into effect.
The desired adjustment of the vehicle bumper assembly 10 may be
accomplished either by turning the collar 44 on the cylinder 32
with the outer end 38 of the piston 36 attached to the bumper beam
14, or by turning the entire energy absorber with the collar 44
attached to the structure 34 and the outer end 38 with the piston
unattached to the bumper beam 14. In either case, after the desired
adjustment has been made, the element which is loose is fastened.
The choice of which method to use depends the configuration of the
vehicle in which the bumper assembly 10 is mounted. In some cases,
the configuration of the available support structure 34 may be such
as to prevent turning of the collar 44. In such a case, the collar
44 is first secured to the structure 34. The entire energy
absorbing devices then turn with the bumper beam 14 being detached
from the piston 36. In such an instance, it is necessary to use a
fixture to determine when the proper amount of adjustment has been
made inasmuch as the bumper facia 16 and end portions 18, 20 will
not be available for visual inspection. The measured amount of
movement of the energy absorbing device 28 per manipulation permits
a predetermination of the amount of turns which are necessary.
In the embodiment shown, the openings are spaced apart on the
flanges at 180 degree intervals. However, it will be appreciated
that other intervals may be used. For example, three, four etc. may
be used as desired. In the present embodiment a one-half turn of
either the collar 44 or energy absorbing device results in the
desired one millimeter advance.
As will be noted in FIG. 2, threaded portions of the collar 44
extend in either direction from the externally threaded portion 40,
thus permitting axial movement in either direction for the desired
adjustment. In an actual embodiment, each of these portions are
about one-half inch for adjustment one-half inch in either
direction. Three eighths of an inch is considered to be the maximum
desired adjustment, the extra increments being provided to
compensate for the initial position of the externally threaded
portion 40 within the collar 44.
* * * * *